Advanced Materials Research Vol. 496

Abstract: The thermoplastic processing and mechanical properties of starch and polycaprolactone (PCL) composites reinforced by nano-silica (nano-SiO₂) were studied. The results showed that the mechanical properties of the starch/PCL blends improved significantly with the increase of PCL. After the addition of nano-SiO₂, the mechanical properties of the starch/PCL blends further improved. When the weight percent of nano-SiO₂ was 1.8%, the mechanical properties of the SiO₂/TPS/PCL composite were most excellent. By comparison with the starch/PCL (50/50) blends, the tensile strength of the SiO₂/TPS/PCL composite with 1.8% SiO₂ was increased by 20% and the elongation increased by 33%. Moreover, it was confirmed by rheological measurements that nano-SiO₂ could interact with the composite materials, which results in the improvement of the mechanical strength of the TPS/PCL composites.

Abstract: We investigated the preparation of porous film of cellulose-based graft copolymer by breath figure method. The effects of substrate, solvent, graft density and graft length on the formation of porous film were elucidated. The results showed that ordered porous films could be facilely formed on the glass and mica substrate, while no ordered porous films were obtained on the silicon substrate. The ordered porous films were formed from the copolymer/CS₂ solution, while no ordered porous films were done from the copolymer/CH₂Cl₂, CHCl₃ and toluene solution. Moreover, no ordered porous films were obtained from the copolymer with spare graft density or with long side chain. The results indicated that the substrate, solvent, graft density and graft length had important effects on the ordered porous film.

Abstract: Methyl orange decoloration was conducted in the solution containing NaHCO3. TiO2 and the mixture of TiO2 and HZSM-5 were used as the photocatalysts. The addition of TiO2 greatly changed adsorption of methyl orange in solutions containing different concentration of NaHCO3. The existence of NaHCO3 can improve photocatalytic degradation of the dye under UV irradiation in the solution containing TiO2. As high as 55% decoloration of the dye occurred in the solution containing 1.0 mol/l NaHCO3. When NaHCO3 concentration was lower than 0.08 mol/l, adsorption of the dye was fairly weak on the mixture. At the same time, decoloration of the dye deceased with increasing NaHCO3 concentration. When NaHCO3 concentration was high, adsorption and decoloration of the dye were better at higher NaHCO3 concentration.

Abstract: Three kinds of templates were used to prepare porous boron doped TiO2 based photocatalysts by sol-gel method. Adsorption of methyl orange on the materials maintained with very slight variation in template adding concentration. With increasing PEG1000 concentration, photocatalytic activity of the material presented obviously variation. The optimal concentration appeared at 0.08 mol/l, where methyl orange degradation rate was 24.7%. When PEG400 concentration was 0.14 mol/l, photocatalytic degradation rate of methyl orange on the material was 17.9%. In the template concentration range from 0.06 mol/l to 0.16 mol/l, degradation activity occurred at CTAB concentration of 0.10 mol/l showed the optimal value of 31.1%, which was the highest among the three kinds of templates.

Abstract: The construction industry is one part of economic development critical to a nation’s infrastructure. However, there is significant man-made “Greenhouse Gas (GHG)” generated during the construction industry’s any Life Cycle (LC).We tailor actions to suit local circumstance and made a systematically preliminary investigation of an inventory, estimation and analysis system currently available in estimation of carbon footprints of an ordinary RC building in Taiwan. There are about 60% of carbon footprints derived from production or usage of high carbon emission building material steel bars.

Abstract: Boron doped TiO2 photocatalysts was prepared by sol-gel method. The influences of Boric acid amount, reaction time and calcination temperature on photocatalytic activity of the prepared B-TiO2 were studied. The boron doped TiO2 had small adsorption capacity. 38.8% of the initial methyl orange was degraded on the sample prepared with 1% B2O3 after 30 min of irradiation. After 120 min of irradiation, nearly 100% of the methyl orange was degraded on the material. Photocatalytic activities of the boron doped TiO2 materials increased from 400 oC up to 500 oC. After that, degradation activity decrease with further increase of calcination temperature in the range from 500 oC to 600 oC.

Abstract: Porous TiO2-Al2O3 composites were prepared through sol-gel method after calcination at 500 oC for different time. PEG1000 was used as a template and tetrabutyl titanate and aluminum isopropoxide were used as the precursors. The materials prepared under different calcination temperatures were all composed of anatase TiO2 and amorphous Al2O3. All the samples presented anatase TiO2 crystalline structure. There was no rutile TiO2 phase appearing in the patterns. Meanwhile, there were no noticeable diffraction peaks of any of crystalline phases of Al2O3. Calculated from Scherrer formula on (101) plane of the XRD patterns, crystallite sizes of anatase TiO2 were 10.06 nm, 10.55 nm, and 11.13 nm, respectively. The surfaces of the materials were very rough with long grooves on the surface. The materials were composed of large amorphous like matrix, along with some small particles laying on the surface.

Abstract: Porous TiO2-Al2O3 composite materials were prepared through sol-gel method after calcination at 500 oC for different time. FT-IR spectra of porous TiO2-Al2O3 composite materials revealed that the samples are composed of Al2O3 and TiO2. The sample calcinated for 2.5 h had the maximum specific area of 128.9 m2•g-1. High pore volume and average pore size were possessed by the samples calcinated for 1 h and 3 h. While being calcinated at 500 oC, photocatalytic activities of the materials increased at first and then dropped down with the increasing calcination time. The sample calcinated for 3 h showed the maximum activity of 35%.

Abstract: Taking the active floridin prepared by mixed acids as absorbent, its absorbability and absorption capacity of lead chrome yellow are studied. The research results indicate that the initial concentration of wastewater is advantageous for improvement of the active floridin absorbability. Larger dosage of active floridin results in greater removal rate of lead chrome yellow but smaller absorbability; higher temperature of the wastewater causes weaker surface absorbability of active floridin and thus the absorbability and removal rate of lead chrome yellow are lower; greater ph value of wastewater brings more severe damage on the lamellar structure of active floridin, as well as lower absorbability and removal rate accordingly.

Abstract: We investigate the coherent transport properties of electrons in a side terminal of a four-terminal nano device made of quantum wires with Rashba spin-orbit (SO) coupling in the presence of magnetic filed. We numerically calculate the charge and spin conductances dependent on SO coupling strength and reduced flux. The results imply that the coherent transport in this device is determined by the interplay of Rashba SO coupling and magnetic filed. For specific values of magnetic flux and SO coupling strength, a complete blocking can take place. It also shows that there is a de-blocking phenomenon induced by the interplay of magnetic flux and SO coupling. Such a 4-terminal and multi-channel structure may provide more options of controlling methods for the coherent charge and spin transport.